Perhaps you should try some spelling variations:
thuoc sach » hoc sach, thuat sach, thuoc sinh
nuoc sach » nguoi sach, hoc sach, cuoc cach
toc sach » hoc sach, doc sach, toc san
vu nang » vuc nang, va nang, vu dang
hieu va » lieu va, hieu qua
cam luc » cam xuc, cau luc
va hanh » van hanh, va thanh, va danh
hanh te » hanh tu, hanh ve, hanh de
cuu tre » cua tre, cau tren, cau treo
va cam » va cham, va cac, va cao
luc va » duc va, tuc va, loc va
te cuu » te cua, te cau, tu cuu
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((((toc sach) or (nuoc sach))) or (thuoc sach)) vu nang x hoi. hieu va cam luc va hanh te cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((toc sach) OR (nuoc sach))) OR (thuoc sach)) vu nang x hoi. hieu va cam luc va hanh te cuu tre.
• Adding a wildcard symbol may retrieve word variants: ((((toc sach) or (nuoc sach))) or (thuoc sach)) vu nang x hoi. hieu va cam luc va hanh te cuu tre*.